Tacx Neo 2T - Tacx Training App now allowing to control resistance/ERG while on Zwift (whereas I was able to do it with the Neo 1)

Why do you want to do this? Do you want to be faster than your opponents? Only one app have to control the trainer if you are in a simulation.

I like to ride in ERG mode and prefer to control the ERG resistance from the app rather than creating an workout in a certain zone that limits the amount of resistance I can increase or decrease to that particular zone. For example when I’m following the B bot, I constantly need to increase my power outside of my endurance zone to keep up with it on rollers after downhills. The app made it easy. Also because I was able to do it with my older Neo (now my wife’s) I would think there is no reason for this feature to not be part of a newer therefore better product. FYI the ERG via the app does not make me go faster by itself. I would think it’s the opposite: it makes the training hard since I have to constantly pedal and therefore drafting/coasting is not a factor. 

I know what you mean, but I think that if you want simulate a ride you don't have to change the target of the trainer manually. 

FYI In a downhill, you can be faster if you have a high target of power, but if you don´t change the target, it´s harder to get it.

So, a solution for you:

1) You can link with Zwift only the powermeter of the Neo 2T, and control it with the Tacx App.

2) Change the Neo for your wife's

;)